I assume this is a 182, but I did my 200 recently. Fill plug is a wing nut on the side of the box. Jacked car up, wriggled around and was able to access. Made sure I could undo before draining.
Drained on slightly warm engine. I measured the drain, just under 2 litres. I got some GL4 75/80 elf stuff off eBay for about £30.
I trimmed a garden hose as unadjusted it didn’t quit fit. I pushed the end of the hose in and gravity fed via hose and funnel 2 litres.
The fill plug is supposed to be the over fill point, but none was particularly dripping out when I did mine, and I didn’t want to open litre 3.
I assume the 182 is the same.